To increase the memory capacity of a nonvolatile semiconductor memory device, a three-dimensional stacked memory has been proposed. The three-dimensional stacked memory includes a stacked body with insulating films and electrode films alternately stacked therein, silicon pillars penetrating through the stacked body in the stacking direction, and a charge accumulation layer (memory layer) provided between the silicon pillar and the electrode film. Thus, a memory cell is provided at the intersection between the silicon pillar and each electrode film. Furthermore, it is also possible to use a U-shaped memory string connecting two silicon pillars on the substrate side.
In such a three-dimensional stacked memory, there is demand for reducing the number of manufacturing steps and reducing the manufacturing cost.